Download presentation
Presentation is loading. Please wait.
Published byAnne Jackson Modified over 9 years ago
1
NOTE: To change the image on this slide, select the picture and delete it. Then click the Pictures icon in the placeholder to insert your own image. WAVES Unit 6
2
THE NATURE OF WAVES Chapter 10 Section 1, Section 2
3
Waves Are Everywhere Waves are everywhere: Microwaves heating your food Ocean waves Sound waves Light waves Can you think of more examples?
4
Waves A wave is a repeating disturbance or movement that transfers energy through matter or space Waves transfer energy Waves do not transfer matter The particles of the matter are only temporarily displaced A force acting upon the particles restores them to their original position The particles of the medium simply vibrate about a fixed position as the pattern of the disturbance moves from one location to another location
5
Types of Waves Mechanical Waves Waves that can only travel through a medium Medium is matter a wave travels through The medium can be solid, liquid, gas, or a combination of the these There are two types of mechanical waves: Transverse waves Compressional waves
6
Mechanical Waves Transverse Waves Matter moves back and forth at a 90 o angle to the direction the wave it travelling
7
Transverse Waves
8
Mechanical Waves Compressional Waves Also called Longitudinal Waves Matter moves back and forth in the same direction the wave it travelling
9
Compressional Waves
10
Parts of a Wave Transverse waves have alternating high points and low point High points crests Low points troughs Compressional waves have tighter compression and looser compression Tight compression compression Lower compression rarefaction
11
Properties of a Wave All waves have a property called wavelength Wavelength is the distance between one point on a wave and the nearest point just like it Crest to Crest Trough to Trough (b) Compression to Compression (a) Rarefaction to Rarefaction
12
Properties of Waves Frequency Number of wavelengths that pass a fixed point each second Frequency is expressed in Hertz (Hz) A frequency of 1 Hz means one wavelength passes a fixed point every second What does 100 Hz mean? 100 wavelength pass a fixed point every 1 second As frequency increases, wavelength decreases.
13
Properties of Waves Period Amount of time it take for one wavelength to pass a point As frequency increases, period decreases. Period is measured in seconds
14
Properties of Waves Wave Speed Speed of a wave depends on the medium it’s travelling through Sound waves usually travel faster in liquid and solids than gases Light waves travel faster in gas or empty space Wave speed can be calculated by the following equation:
15
Properties of Waves Amplitude Related to the energy transferred by a wave For a compression wave High amplitude waves Tighter compressions (more dense) For a transverse wave High amplitude waves Taller peaks
16
Water Waves Water waves are not purely transverse waves Water waves also have some longitudinal motion The result is particles of water following a circular motion pattern Objects floating on the surface of water will also bob in a circular motion
17
Water Waves
18
How Are Water Waves Formed Wind causes ripples to form on the surface of the water With energy of the wind is being transferred to the surface of the wind The waves will depend on the length of time and the distance over which the wind blows as well as the wind speed Ocean Waves
19
Seismic Waves When a guitar spring breaks, it vibrates for a short time and produces sound waves When the Earth’s crust shifts, bends, or breaks, the crust vibrates creating seismic waves Seismic waves are also combinations of compressional and transverse waves When objects on the Earth’s surface absorb some of the energy in seismic waves, they move and shake causing an earthquake Earthquakes
20
Deadliest Earthquakes Video NOVA: Deadliest Earthquakes NOVA: Deadliest Earthquakes
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.